Visualizing highly cited scientific output of Indian physiotherapists: A bibliometric study

Background: Physiotherapy research supports the advancement of evidence-based practice and the development of a highly skilled workforce. This study aims to visualize the highly cited scientific output of Indian physiotherapists from 1999 to 2018. Methods: A descriptive study design was adopted to visualize the highly cited scientific output of Indian physiotherapists using the Web of Science (WoS) database from 1999 to 2018. A search was carried out using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018”. Data collected were analyzed using Incites from WoS and VOSviewer software. Results: A total of 488 articles were published between 1999 and 2018, with a peak of 103 in 2016 with 2419 citations. A decline in publication count was observed after 2016. The journal International Journal of Physiotherapy published the highest number of articles (n=35). Manipal University (n=36) was found to be the most active institution for physiotherapy research in India, as determined by publishing the most articles. Indian physiotherapists published the highest number of research articles in collaboration with US authors (n=24). Conclusion: There is an increasing trend in the scientific output of Indian physiotherapists over the past two decades; however, a decline is observed after 2016. It is recommended that research collaborations across the globe are increased and scientific output should be improved, leading to a higher number of citations. Future research should explore factors influencing the scientific production of Indian physiotherapists and devise appropriate strategies to attain further improvement.

There is an increasing trend in the scientific output of Indian Conclusion: physiotherapists over the past two decades; however, a decline is observed after 2016. It is recommended that research collaborations across the globe are increased and scientific output should be improved, leading to a higher

Introduction
The scientific output of a profession is recognized by the frequency of publications, which are published in peer-reviewed journals and indexed in bibliographic databases [1][2][3] . In physiotherapy, this scientific output is utilized to enhance existing knowledge and develop guidelines for highly effective clinical practice 4 . Accordingly, the analysis of scientific output allows the definition of baseline indicators in knowledge and clinical practice in physiotherapy 5,6 . Various studies investigated the scientific output of physiotherapists across the globe 6-14 . Among these studies, several utilized electronic searches 6,7,9-11,13,14 , whereas others were limited to document reviews 8,12 . Concerning the Indian context, only two studies have been performed to reveal the research productivity of Indian physiotherapists from 2000 to 2014, which were limited to the Medline database 10,11 . Moreover, Li et al. (2018) recently stated that Clarivate Analytics's Web of Science (WoS) is the World's foremost scientific citation search and analytical platform, which can be used as both a research tool and dataset 15 . Hence, there is a need for further research that should involve the WoS database to detect high-quality research publications by Indian physiotherapists until 2018. Therefore, this study was planned to conduct a bibliometric study on the scientific output of Indian physiotherapists using WoS during the last two decades (from 1999 to 2018).

Methods
The descriptive study design was adopted to reveal the scientific output of Indian physiotherapists using an electronic literature search in the WoS database during the period from 1999 to 2018.

Article selection
The search was conducted on 14th October 2019. The term 'Indian physiotherapists' denotes physiotherapy professionals employed in any of the academic or clinical establishments in India in the study period. The search was carried out in WoS using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018". The search started from 1999 since this study aimed to retrieve data from the past two decades.

Article screening
The search methodology is described in Figure 1. Based on the inclusion criteria, 488 publications were included and proceeded for further analysis.

Data analysis
Retrieved articles were analyzed using Incites in WoS and Visualization of Similarities (VOS) viewer 1.6.11. VOS is a new method used for visualizing similarities between objects 16,17 .
Incites was used to gather information on publication year, authorship ranking, source journal productivity, collaborating institutions, country-wise research collaboration, citations, and collaboration pattern of articles. In addition, the information related to h-index was obtained from the Incites in WoS. Here, the h-index reflects the productivity of authors based on their publication and citation records. It is useful because it discounts the disproportionate weight of highly cited papers or papers that have not yet been cited. The data, which is exported from the WoS database as an ISI common export (.ciw) format, were imported into VOSviewer to explore the co-occurrences of keywords used by the authors in their articles. The flowchart describing the procedures for carrying out both Incites and VOSviewer analysis is depicted in Figure 2.
Since Incites in WoS used in this study is a proprietary software, the researchers could alternatively use a tab-delimited file downloaded from WoS and use it in VOSviewer.

Results
A total of 488 articles were included in the study; 381 research articles, 53 reviews, 34 proceedings, 9 meeting abstracts, 8 letters, and 3 editorial materials. The chosen period of study was divided into four strata with five years each. The strata were 1999-2003; 2004-2008; 2009-2013; and 2014-2018. In the first two strata, the publication count was observed in a single digit (≤9). In the third strata, this count has reached two digits with a maximum of 26 in 2013. However, in the fourth strata, an abrupt rise in the publication count was observed with a peak of 103 in 2016. Notably, the publication counts after 2016 decreased and rose slightly in 2018, but not to those levels seen in 2016 (Table 1 and Figure 3). Regarding citation count, there was a gradual rise over the research period, with a total of 2419 citations between 1999 and 2018, more than 100 of which have been documented since 2012. The highest average citation (citations/article) of ≥10 was observed only in 2006 (mean, 11.00) and 2014 (mean, 10.20).
A total of 264 journals had published the 488 retrieved articles. The top 20 journals in which Indian physiotherapists

Amendments from Version 1
In response to the reviewers' comments, the previously published version of this article was revised with appropriate responses. The new version of this article includes the revised abstract, manuscript text, tables, figures, data link, and references. The previously submitted tables and figures are updated with new data since one correction article was removed. Additionally, the three new tables, such as the collaboration patterns of articles, the top 10 highly cited papers of Indian physiotherapists, and the top 20 keywords are provided. Moreover, two new figures depicting the information about the top 10 collaborating countries and the top 10 authors collaboration are added using VOSviewer. A new heading "Limitations and Recommendations" has been added to describe the limitations and further recommendations of this study. All tables and figures are provided in the revised link (Version 2) of Open Science Framework in the same order as they appear in Version 2 of the manuscript. Also, seven additional supporting literature is added to strengthen the findings and are listed in the reference section. English language editing has already been carried out to improve the clarity of the readers. published over the study period are displayed in Table 2. The top 20 journals published 174 articles i.e., 35.66% of total publications (N=488) in the research period. Out of the top 20 ranked journals, 11 were journals based in India, 26.79% of the total publications.
The International Journal of Physiotherapy published 35 articles, with six citations for these 35 articles, an average citation per article as 0.17. It was the most active journal found in this study and contributed to 7.17% of total publications. In contrast, the journal Haemophilia published seven articles with 68 citations for these articles, an average citation of 9.71. Similarly, Annals of Indian Academy of Neurology published four articles, with citations of 43, giving it the highest average citation of 10.75 (Table 2). Table 3 shows the top 20 authors who worked with Indian physiotherapists to publish physiotherapy articles. These authors contributed 22.13% of total publications (N=488) in collaboration with Indian physiotherapists. Kumar S, Mahadevappa M, and Samuel AJ collectively have accounted for 5.74% of total publications (N=488). An Indian author named Kumar R (ICMR-National Institute of Occupational Health) is the Indian physiotherapist with the highest h-index (18) and had published five articles, which were cited 1372 times. The citations per article of that particular author was observed as high of 274.40. Further, the type of author collaboration was explored and the year-wise collaboration pattern of the articles was presented in Table 4. Out of 488 publications, 27.05% of articles were published by five and above authors, and 5.5% by a single author.
The top 20 institutions collaborating with Indian physiotherapists for physiotherapy research are displayed in Table 5. Among these institutions, Manipal University (India) has the highest number of publications, with 7.38% of total publications, followed by Christian Medical College Hospital (India; 3.89%), the Indian Institute of Technology (India; 3.69%) and King Saud University (KSU; Saudi Arabia; 3.69%). In total, 90% of collaborating institutions were based in India. Internationally, KSU and the University of London (UK; 1.23%) had the most active cooperation with Indian physiotherapists over this time period.
Out of the total publications (N=488), articles published by Indian physiotherapists in collaboration with authors belonging to international countries was as follows: United States (4.92%), Saudi Arabia (4.51%), UK (3.69%), Canada (1.84%), and Sweden (1.02%). Italy, Pakistan, Brazil, Australia, Malaysia, and Mexico contributed 0.82% each to total publications ( Table 6). Out of the top 20 countries, Indian physiotherapists collaborated the most with the US (after India), publishing 24 articles, which secured 370 citations (average citation 15.42). Notably, articles published by Indian physiotherapists in collaboration with   Using VOSviewer, the top 20 keywords used in articles (from a total of 2477 keywords) are shown in Figure 4. An article's keyword may represent its primary material, and to some degree, the frequency of occurrence 18 . Likewise, co-occurrence can indicate centered themes of research in a field. Through VOSviewer, the authors observed top 20 keywords and it is shown in Table 8. Among the top 20 keywords, the minimum number of occurrences of each keyword was set to 11 and excluded the keyword "Physiotherapy," "Rehabilitation," and "Physical Therapy" from the formation of the cluster. There were three co-citation clusters formed using this criterion. The results showed that the keyword "Management (cluster 1 red color)" had the highest linkages (N=50) with all the 3 clusters, followed by keywords "Exercise (cluster 2 green color)" and "Reliability (cluster 3 blue color)" had 40 and 39 linkages respectively with all 3 clusters. Besides, the collaboration observed among the top 10 authors and top 10 countries were presented in Figure 5 and Figure 6 respectively. Concerning the top 10 authors collaboration, co-authorship network analysis produced a map for authors with at least four papers and formed six clusters. The most profile authors in terms of citation were observed as Kumar R and Mahadevappa M. These authors showed more collaboration. Furthermore, network visualization of countries with a minimum of four papers showed the top 10 countries in three clusters. The following pairs of countries showed a strong collaboration between them: India-USA (link strength =22), India-Saudi Arabia (link strength=22), and India-England (link strength=17).

Publication count
Using the Scopus database, a recent study had observed that Italian physiotherapists published 1083 articles from the year 1995 to 2016. More than 50% of the total publications were

Journals
Notably, this study observed that Indian-based journals published 26.84% of the total publications (N=488); no publications were observed in US-based journals. Further, the highest count of publications was observed in an Indian-based journal     International Journal of Physiotherapy. This affinity of Indian physiotherapy researchers towards Indian-based journals might be due to the nature of their research articles, or interest in country-based journals. However, those researchers should expand their contribution to other high-quality international journals. Exploring the reasons behind Indian physiotherapists' choice to publish in these Indian journals is beyond the scope of this study, and further research is warranted to address this critical issue. In general, the choice of researchers to publish in a journal depending on the prestige, impact factor, quality of peer reviews, acceptance rate, readership, article publishing charges, and reputation to the scientific community 19,20 . Besides, the journals, such as Haemophilia and Annals of Indian Academy of Neurology, showed considerable citations and a high average citation for only a few articles published in these journals. This implies that these articles might be more useful for the researchers to cite them often 21 . Keywords by co-occurrence Dash et al. stated that the keywords are one of the three pillars of a biomedical research article. Using the right keywords would augment the article being found by other researchers as these are used by abstracting and indexing services 28 . Hence, this study revealed the top 20 keywords that occurred in various articles using VOSviewer software. It is observed that the keyword "Management" had the highest of 50 linkages with all the three co-citation clusters.

Conclusion
This study observed that the scientific output of Indian physiotherapists shows an uptrend in performance since 1999, excluding 2017 and 2018, where a considerable decline was noticed. The results showed that Indian physiotherapists had mostly published in Indian-based journals, and collaborated with Indian institutions. Even though there are high-quality publications, there is a need to enhance both the quality and quantity of scientific papers to increase the high number of citations and average citations. This study also recommends that Indian physiotherapists should expand their research collaboration internationally to improve their scientific output.

Limitations and recommendations
The findings of this study are only limited to the WoS database. Future research can focus on studying the research output of the Indian physiotherapists in other databases to ascertain their research productivity. Future studies can also focus on analyzing individual and institutional factors influencing the research productivity of Indian physiotherapists and develop suitable strategies to enhance their scientific production. 1.

Open Peer Review Current Peer Review Status:
Version 2 17 June 2020 Reviewer Report https://doi.org/10.5256/f1000research.26175.r61695 © 2020 Vaidhiyalingam P. This is an open access peer review report distributed under the terms of the Creative , which permits unrestricted use, distribution, and reproduction in any medium, provided the Commons Attribution License original work is properly cited.

Prakash Vaidhiyalingam
Ashok and Rita Patel Institute of Physiotherapy, Charotar University of Science and Technology, Changa, Gujarat, India Its a well conceived study exploring key metrics of research work published by Indian Physiotherapists. I think citation-metrics data provided by the authors can be very useful to understand and analyse the publication trend and research productivity of Indian Physiotherapists.
Key issues: I find the title and the aim is somewhat misleading. The study provided an in-depth citation analysis of all research work published by Indian PTs in the WoS indexed journals not just 'highly cited' articles. An additional/sub analysis highlighted top 20 publications.
The authors's attempt at reviewing High-quality research indexed in WoS is justifiable. I found two major issues related to how high quality is defined in this study and how it is interpreted: High-quality journal or publication is not clearly defined. I suggest a brief discussion on using citation metrics and indexing databases as a criteria for research quality to be included in Introduction Inclusion of journals in Emerging Sources Citation Index (ESCI) need clarification. Journals indexed in ESCI is monitored for quality by WoS but unlike the journals indexed in SCIE it doesn't have impact factor. My suggestion is authors may consider adding a brief note on discussing potential confounding effect of adding multiple journal indexes of SCI. I also think the acronyms (SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC) need to be expanded and a brief description of each would help reader to understand similarities and differences among them. based on the affiliation details given in the article. How did the authors of this article confirmed? I suggest authors to verify other articles too.
Discussion can be more structured with less data and more interpretation of data.

Is the work clearly and accurately presented and does it cite the current literature? Yes
Is the study design appropriate and is the work technically sound? Yes

If applicable, is the statistical analysis and its interpretation appropriate? Yes
Are all the source data underlying the results available to ensure full reproducibility? Yes

Aamir Raoof Memon
Institute of Physiotherapy and Rehabilitation Sciences, Peoples University of Medical and Health Sciences for Women, Nawabshah, Pakistan I enjoyed reading the bibliometric analysis of scientific output of physiotherapists from India. The manuscript is interesting but requires improvement in its content. My suggestions are given below: manuscript is interesting but requires improvement in its content. My suggestions are given below:

Abstract:
: Author 1 "….determined by producing the most articles" should be revised to "determined by the most articles" publishing Introduction: : Author 2 "…….Indian physiotherapists up until 2018 (this study took place in 2019)" please delete "(this study took place in 2019)" : Author 3 "…..this study intended to conduct a bibliometric…." should be revised to "this study was planned to conduct a bibliometric"

:
Author 5 Instead of "physical rehabilitation", authors could have used "rehabilitation". Also, authors could use the term "exercise therapy" or "manual therapy" or "manipulative therapy" because not all papers use the terms physical therapy or physiotherapy. Please add space between "AND" and "AD".

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Author 7 I think there is a typo here "……to gather information…." and should be revised to "…..to gather information on…".

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Author 8 Inclusion criterion 3 (Fig 1) should be "publications with at least one physiotherapist with institutional/author affiliation from India listed as a co-author". In addition (related to criterion 1), did the authors include peer-reviewed journal publications or meeting abstracts and other document types?
Author 9: What is the significance of adding "Correction"? The common practice is that this category of papers is EXCLUDED from the analysis.
Author 10: "……the information related to h-index was obtained from the Incites in WoS": please explain h-index and its use here.
Author 11: Please explain the VOS parameters used and cite their original source.
Author 12: "…..used in this study are proprietary…" should be "…..used in this study is a proprietary…." Author 13: Statistical analysis should present the bibliometric parameters in detail.

Results:
Author 14: "Between 1999 and 2008…." this paragraph should be in the past tense, please revise.
Author 17: "average citation of 0.17" should be revised to "average citation per paper as…".
Author 18: Fig 2: Please check the heading for Flowchart for VOSviewer analysis -I suspect some errors there.
Author 19: Table 1  . https://www.ncbi.nlm.nih.gov/pubmed/31766944 https://doi.org/10.3390/clockssleep2020010 Author 21: Table 2-5: I think it would be appropriate to list the top 10 instead of 20 -again, this is a common practice in bibliometric studies. I would also want to see top-10 highly cited papers.
Author 22: Table 2: It would be interesting to discuss the impact factor and SJR ranking ( ) of these journals. This will reflect the quality and https://www.scimagojr.com/journalrank.php visibility of these journals. I see that most of these journals are indexed in the ESCI -the lowest level of WoS indexes.  Table 4" -this does not look grammatically correct and needs revision. These could be organized in two tables as national (within India) and international (outside India) collaborations.
Author 26: It would be better to exclude "Physiotherapy" and "Rehabilitation" from the map because they will certainly be the most used. The readers of this paper would rather be interested to see what other terms had frequent occurrence. The authors should also discuss the map (Fig 4) to reflect upon which keywords tend to occur together. For instance, keywords in green (i.e. management, trial, children, diagnosis, surgery, India) tend to belong to the same cluster and are likely to co-occur together. What was the minimum value set for the co-occurrence of a keyword? For example, see this paper: . https://www.ncbi.nlm.nih.gov/pubmed/31766944 Author 27: Table 3: the column for h-index should come to the right of total citations. Iqbal ZA does not have Indian affiliation, so these names don't correspond well with the caption of the table. I believe these could be organized in two tables as national (within India) and international (outside India) collaborations. If this is not possible then the authors are advised to revise the caption of the Author 28: Table 4: Please revisit the caption for clarity. Authors should add a column "collaboration" and categorize it as national and international.
Author 29: Table 5: Six institutions with 4 papers are presented but I don't understand how they are ranked (according to the number of citations or citations/paper). As of now, it appears as if they are listed alphabetically. The common method in bibliometric studies is to rank them based on the number of citations.

Discussion:
Author 30: Overall, this section is just the repetition of the results and fails to integrate what is known about the topic and what was found.
Author 31: Concerning these two points: "Exploring the reasons…..critical issue" and "This implies that……other researchers". These are vague arguments -I believe that this would be due to several factors, including the quality of the journal (indexing, metrics), ease of publication (acceptance rate), focus (audience/readership), APCs and reputation to the scientific community. I think authors have failed to give a balanced view here. Most of these journals appear to be of low-quality. Just a point for your understanding is that the IJPT was once involved in deceptive practices (please see this paper: ) , but it has https://www.ncbi.nlm.nih.gov/pubmed/27924967 probably improved its practices and has gotten into ESCI.
Author 32: Collaborating authors: It would be appropriate to discuss the average h-index (and its range) and average citations to the papers by Indian authors.
Author 33: I still have confusion regarding the organization and presentation of findings of this paper in the results and discussion sections. Collaborating authors, institutions, and countries should have been leading authors, institutions and countries. Collaborations between countries, institutions, and authors should better be presented through VOSviewer as done in these papers: ; . https://www.ncbi.nlm.nih.gov/pubmed/31766944 https://doi.org/10.3390/clockssleep2020010 Author 34: What is the clinical implication of these keywords? Please discuss.
Author 35: Please add a section about the limitations of this study.

Conclusions:
Author 36: The decrease in papers during 2017 and 2018 was not "drastic", please rephrase this.
Author 37: "…….though there are high-quality publications…" this stands as a mere claim and won't be meaningful without presenting the top-10 highly cited publications.

Language & grammar:
Author 38: I noticed grammatical errors at several places, please revise accordingly. PubMed Abstract

If applicable, is the statistical analysis and its interpretation appropriate? Partly
Are all the source data underlying the results available to ensure full reproducibility? Yes

Are the conclusions drawn adequately supported by the results? Partly
No competing interests were disclosed.

Competing Interests:
Reviewer Expertise: Physical activity, rehabilitation, exercise, scientometrics, bibliometric analyses I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.
Author Response 09 May 2020 , Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Arun Vijay Subbarayalu REVIEWER 2 Abstract: Author 1: "….determined by producing the most articles" should be revised to "determined by publishing the most articles" The correction has been incorporated in the manuscript (Refer Results section of the Abstract). Under the Results section of the Abstract, it is written as follows: Manipal University (n=26) was found to be the most active institution for physiotherapy research in India, as determined by publishing the most articles.

Author 2: "…….Indian physiotherapists up until 2018 (this study took place in 2019)" please delete "(this study took place in 2019)"
The term "this study took place in 2019" is deleted in the Introduction of the manuscript. Under Introduction, it is written as follows: Hence, there is a need for further research that should involve the WoS database to detect high-quality research publications by Indian physiotherapists until 2018.

Author 3: "…..this study intended to conduct a bibliometric…." should be revised to "this study was planned to conduct a bibliometric"
The correction has been incorporated in the text of the manuscript.
Under Introduction, it is updated as follows: Therefore, this study was planned to conduct a bibliometric study on the scientific output of Indian physiotherapists using WoS during the last two decades (from 1999 to 2018).
The correction has been incorporated in the Abstract and Methods sections of the manuscript. Under Methods section of the Abstract, following updates has been carried out: A search was carried out using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018".

Under "Article Selection" of the Methods section
The search was conducted on Oct 14 2019. The term 'Indian physiotherapists' denotes physiotherapy professionals employed in any of the academic or clinical establishments in India in the study period. The search was carried out in WoS using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018". The search started from 1999 since this study aimed to retrieve data from the past two decades.
Author 5: Instead of "physical rehabilitation", authors could have used "rehabilitation". Also, authors could use the term "exercise therapy" or "manual therapy" or "manipulative therapy" because not all papers use the terms physical therapy or physiotherapy. Please add space between "AND" and "AD".

The search conducted based on TS=" physiotherapy" TS means Topic
We have initially tried our search using all these alternative keywords, i.e., 'rehabilitation', which brought lots of irrelevant content that was not related to physiotherapy rather related to other medical rehabilitation, after that we have excluded the term "rehabilitation" from our search term.
Likewise, while using the keyword "manual therapy" or "manipulative therapy," as of today, we got 510 articles with very meager differences, and few of them irrelevant to physio records. Even we noticed a few extra articles were also added in WoS using our same previous search.
Next, the space between "AND" and "AD" is added in the Abstract and Methods sections of the manuscript.

Under "Article Selection" of the Methods section
The search was conducted on Oct 14 2019. The term 'Indian physiotherapists' denotes physiotherapy professionals employed in any of the academic or clinical establishments in India in the study period. The search was carried out in WoS using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018". The search started from 1999 since this study aimed to retrieve data from the past two decades.

, instead of Article Selection paragraph under the Methods section (This is done as it is a medium-sized article where we need to fit into
). the word count provided by the Journal Author 7: I think there is a typo here "……to gather information…." and should be revised to "…..to gather information on…".
The correction has been incorporated in the text of the manuscript.

The correction has been incorporated in the text of the manuscript. Under Data Analysis of the Methods section
Incites was used to gather information on publication year, authorship ranking, source journal productivity, collaborating institutions, country-wise research collaboration, citations, and collaboration pattern of articles. Also, the information related to h-index was obtained from the Incites in WoS.
Author 8: Inclusion criterion 3 (Fig 1) should be "publications with at least one physiotherapist with institutional/author affiliation from India listed as a co-author". In addition (related to criterion 1), did the authors include peer-reviewed journal publications or meeting abstracts and other document types?
The authors have updated the correction in Figure 1. With regard to criterion 1, we have included all types of documents, not restricted to peer-reviewed journal publications.
Author 9: What is the significance of adding "Correction"? The common practice is that this category of papers is EXCLUDED from the analysis.
As suggested, one item excluded as it is a correction article, and all the tables & graphs updated accordingly.

Author 10: "……the information related to h-index was obtained from the Incites in WoS": please explain h-index and its use here.
We have added the following information concerning h-index in "Data Analysis" of the methods section: Under Data Analysis of the Methods section, we have updated it as follows: In addition, the information related to h-index was obtained from the Incites in WoS. Here, the h-index reflects the productivity of authors based on their publication and citation records. It is useful because it discounts the disproportionate weight of highly cited papers or papers that have not yet been cited.

Author 11: Please explain the VOS parameters used and cite their original source.
We have added the following literature source to cite VOC parameter within the manuscript: Under Data Analysis of the Methods section, we have updated it as follows: Retrieved articles were analyzed using Incites in WoS and Visualization of Similarities (VOS) viewer 1.6.11. VOS is a new method used for visualizing similarities between objects . Author 12: "…..used in this study are proprietary…" should be "…..used in this study is a proprietary…." The required correction carried out. The word 'is a' has been added in front of the word 'proprietary software'.
Under Data Analysis of the Methods section, we have updated it as follows: Since Incites in WoS used in this study is a proprietary software, the researchers could alternatively use a tab-delimited file downloaded from WoS and use it in VOSviewer.

Author 13: Statistical analysis should present the bibliometric parameters in detail.
We have included bibliometric parameters related to publication year, authorship ranking, source journal productivity, collaborating institutions, country-wise research collaboration, citations, and h-index. As suggested by the reviewer, we have added a year-wise collaboration pattern of the articles as an additional parameter (Table 4).
Refer to the following table caption in the text of the manuscript.

Results:
Author 14: "Between 1999 and 2008…." this paragraph should be in the past tense, please revise.
The respective paragraph has been revised and presented in the past tense. The revised paragraph is provided in the Results section as follows: Under the Results section The chosen period of study was divided into four strata with five years each. The strata were 1999-2003; 2004-2008; 2009-2013; and 2014-2018. In the first two strata, the publication count was observed in a single digit (≤9). In the third strata, this count has reached two digits with a maximum of 26 in 2013. However, in the fourth strata, an abrupt rise in the publication count was observed with a peak of 103 in 2016. Notably, the publication count after 2016 decreased and rose slightly in 2018, but not to those levels seen in 2016 (Table 1 and Figure 3). Regarding citation count, there was a gradual rise over the research period, with a total of 2419 citations between 1999 and 2018, more than 100 of which have been documented since 2012. The highest average citation (citations/article) of ≥10 was observed only in 2006 (mean, 11.00) and 2014 (mean, 10.20).
The correction has been incorporated in the text of the manuscript.
Under the Results section as follows: Under the Results section as follows: A total of 264 journals had published the 488 retrieved articles. The top 20 journals in which Indian physiotherapists published over the study period are displayed in Table 2. The top 20 journals published 174 articles, i.e., 35.66% of total publications (N=488) in the research period. Out of the top 20 ranked journals, 11 journals were based in India, 26.84% of the total publications. Author 16: "…11 were journals based" should be revised to "…..11 journals were based".
The correction has been incorporated in the text of the manuscript. Under the Results section as follows: A total of 264 journals had published the 488 retrieved articles. The top 20 journals in which Indian physiotherapists published over the study period are displayed in Table 2. The top 20 journals published 174 articles i.e., 35.66% of total publications (N=488) in the research period. Out of the top 20 ranked journals, 11 journals were based in India, 26.84% of the total publications. In the flow chart, we have mentioned the subject, and, in the graph, we have indicated the keyword. To address this issue, we have updated the Figure 2 by providing the following corrections on it.
In the heading box "Flowchart….VOSviewer software", we changed the term "co-occurrence of subjects" to "co-occurrence of keywords." The heading in the second box of figure 2, we changed the term "co-occurrence of subjects" to "co-occurrence of keywords." In addition, in Step-5 box of Figure 2, the number 489 is replaced with 488.
Author 19: Table 1 (please cross- As advised, we have added the following description in the results section:

Under the Results section
The chosen period of study was divided into four strata with five years each. These strata were 1999-2003; 2004-2008; 2009-2013; and 2014-2018. In the first two strata, the publication count was observed in a single digit (≤9). In the third strata, this count has reached two digits with a maximum of 26 in 2013. However, in the fourth strata, an abrupt rise in the publication count was observed with a peak of 103 in 2016. Notably, the publication count after 2016 decreased and rose slightly in 2018, but not to those levels seen in 2016 (Table 1 and Figure 3). The corresponding figure 3 is modified as the same provided in the example study. Also, the figure caption is revised as follows: Figure 3. The growth trend for publications and citations by Indian physiotherapists between 1999 and 2018.
Author 21: Table 2-5: I think it would be appropriate to list the top 10 instead of 20 -again, this is a common practice in bibliometric studies. I would also want to see top-10 highly cited papers.
The focus of our study is to review the results based on the top 20 journals, authors, institutions, and countries collaborating with Indian physiotherapists. However, as per the reviewer's feedback, we have provided information about the top 10 highly cited papers in Table 7 of the manuscript. The description of the top 10 highly cited articles is provided in the Results and Discussion section.
Under the Results section, we have updated it as follows: Besides, the top 10 highly cited papers during the study period were provided in Table 7 (Refer Table 7 Author 22: Table 2: It would be interesting to discuss the impact factor and SJR ranking (https://www.scimagojr.com/journalrank.php) of these journals. This will reflect the quality and visibility of these journals. I see that most of these journals are indexed in the ESCIthe lowest level of WoS indexes.
This study is focused on revealing the scientific output of Indian physiotherapists in the WoS database during the period from 1999 to 2018. The criteria have been fixed that this study is limited to the WoS database, and the Web of Science indexes covered was mentioned in the search items (i.e., SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC). As advised by the reviewer, the h-index, JCR impact factor and SJR ranking of the observed journals are additionally provided in Table 2 (Refer Table 2 Table 4" -this does not look grammatically correct and needs revision. These could be organized in two tables as national (within India) and international (outside India) collaborations.
The corresponding sentence is revised for grammatical correction and provided in the Results section.
Under Results, we have updated it as follows: The top 20 institutions collaborating with Indian physiotherapists for physiotherapy research are displayed in Table 5.
In addition, the authors have added a column titled "Collaboration" in Table 5 to mention the collaborating institutions as "National" or "International" (Refer Table 5).
As advised, the reference for the following sentence "An article's keyword may represent its primary….." is provided in the Results section.

Under the Results section
An article's keyword may represent its primary material, and to some degree, the frequency of occurrence .
Author 26: It would be better to exclude "Physiotherapy" and "Rehabilitation" from the map because they will certainly be the most used. The readers of this paper would rather be interested to see what other terms had frequent occurrence. The authors should also discuss the map (Fig 4) to reflect upon which keywords tend to occur together. For instance, keywords in green (i.e., management, trial, children, diagnosis, surgery, India) tend to belong to the same cluster and are likely to co-occur together. What was the minimum value set for the co-occurrence of a keyword? For example, see this paper: https://www.ncbi.nlm.nih.gov/pubmed/31766944.1 The authors have discussed the map (Figure 4) to reflect upon which keywords tend to occur together. They have also described the minimum value set for the co-occurrence of a keyword. The description is provided in the Results section (Also Refer to Figure 4 and Table 8).
Under the Results section, it is updated as follows: Using VOSviewer, the top 20 keywords used in articles (from a total of 2477 keywords) are shown in Figure 4. An article's keyword may represent its primary material, and to some degree, the frequency of occurrence . Likewise, co-occurrence can indicate centered themes of research in a field. Through VOSviewer, the authors observed the top 20 keywords, and it is shown in Table 8. Among the top 20 keywords, the minimum number of occurrences of each keyword was set to 11 and excluded the keyword "Physiotherapy," "Rehabilitation," and "Physical Therapy" from the formation of the cluster. There were three co-citation clusters formed using this criterion. The results showed that the keyword "Management (cluster 1 red color)" had the highest linkages (N=50) with all the 3 clusters, followed by keywords "Exercise (cluster 2 green color)" and "Reliability (cluster 3 blue color)" had 40 and 39 linkages respectively with all 3 clusters.
Author 27: Table 3: the column for h-index should come to the right of total citations. Iqbal ZA does not have Indian affiliation, so these names don't correspond well with the caption of the table. I believe these could be organized in two tables as national (within India) and international (outside India) collaborations. If this is not possible then the authors are advised to revise the caption of the table to bring more clarity in it.
As advised, in Table 3, we have relocated the h-index column to the right side of the total citations column. The new column "citations per article" is also added. In addition, Table 3 caption has already been edited as follows: Table 3. Top 20 Authors collaborated between 1999 and 2018.
Author 28: Table 4: Please revisit the caption for clarity. Authors should add a column "collaboration" and categorize it as national and international.
Table 4 is changed into Table 5. We have changed the caption of Table 5 as "Top 20 institutions collaborating with Indian physiotherapists between 1999 and 2018. A new column, "collaboration," has been added to categorize the institutions as national or international collaboration (Refer to Table 5). 18 18 Author 29: Table 5: Six institutions with 4 papers are presented, but I don't understand how they are ranked (according to the number of citations or citations/paper). As of now, it appears as if they are listed alphabetically. The common method in bibliometric studies is to rank them based on the number of citations. Table 5 is renamed as Table 6. The order of the collaborating countries is listed on the basis of the number of articles. Further, the countries with similar number of articles are ranked based on the number of citations and it is presented in Table 6.

Discussion:
Author 30: Overall, this section is just the repetition of the results and fails to integrate what is known about the Topic and what was found.
As advised, the discussion is revised to avoid the repetition of the results and integrate what is know about the Topic and what was found.
Author 31: Concerning these two points: "Exploring the reasons…..critical issue" and "This implies that……other researchers". These are vague arguments -I believe that this would be due to several factors, including the quality of the journal (indexing, metrics), ease of publication (acceptance rate), focus (audience/readership), APCs and reputation to the scientific community. I think authors have failed to give a balanced view here. Most of these journals appear to be of low-quality. Just a point for your understanding is that the IJPT was once involved in deceptive practices (please see this paper: https://www.ncbi.nlm.nih.gov/pubmed/27924967)3, but it has probably improved its practices and has gotten into ESCI.
As suggested, we have modified the sentence as follows: Under the heading "Journals" in the Discussion section, we have updated it as follows: Exploring the reasons behind Indian physiotherapists' choice to publish in these Indian journals is beyond the scope of this study, and further research is warranted to address this critical issue. In general, the choice of researchers to publish in a journal depending on the prestige, impact factor, quality of peer reviews, acceptance rate, readership, article publishing charges, and reputation to the scientific community .
Under the heading "Journals" in the Discussion section, we have updated it as follows: As the journals such as Haemophilia and Annals of Indian Academy of Neurology with a considerable citation and a high average citation for only a few articles, the authors mentioned the following sentence: This implies that these articles might be more useful for the researchers to cite them often .
Author 32: Collaborating authors: It would be appropriate to discuss the average h-index (and its range) and average citations to the papers by Indian authors.
As the average h-index and average citations to the papers by Indian authors were not observed, this study described the range of h-index and total citations of the top 20 authors. A description is provided under the heading 'Collaborating authors' in the discussion section as follows: 19,20 Collaborating authors

Under Results section
Besides, the collaboration observed among the top 10 authors and top 10 countries were presented in figures 5 and 6 respectively. Concerning the top 10 authors collaboration, co-authorship network analysis produced a map for authors with at least four papers and formed six clusters. The most profile authors in terms of citation were observed as Kumar R and Mahadevappa M. These authors showed more collaboration. Furthermore, network visualization of countries with a minimum of four papers showed the top 10 countries in three clusters. The following pairs of countries showed a strong collaboration between them: India-USA (link strength =22), India-Saudi Arabia (link strength=22), and India-England (link strength=17).
Author 34: What is the clinical implication of these keywords? Please discuss.
The clinical implications of the keywords were discussed with the appropriated literature under the heading "Keywords by co-occurrence" in the Discussion section.
Refer to the heading "Keywords by co-occurrence" in the Discussion section Dash stated that the keywords are one of the three pillars of a biomedical research article. et al. Using the right keywords would augment the article being found by other researchers as these are used by abstracting and indexing services . Hence, this study revealed the top 20 keywords that occurred in various articles using VOSviewer software. It is observed that the keyword "Management" had the highest of 50 linkages with all the three co-citation clusters.
Author 35: Please add a section about the limitations of this study. As advised, a new heading "Limitations and Recommendations" is added in the manuscript.

Limitations and Recommendations
The findings of this study are only limited to the WoS database. Future research can focus on studying the research output of the Indian physiotherapists in other databases to ascertain their research productivity. Future studies can focus on analyzing individual and institutional factors influencing the research productivity of Indian physiotherapists and develop suitable strategies to enhance their scientific production.

Conclusions:
Author 36: The decrease in papers during 2017 and 2018 was not "drastic", please rephrase this.
The term "drastic" is revised and described as follows in the Conclusion section.

Conclusion
This study observed that the scientific output of Indian physiotherapists shows an uptrend in performance since 1999, excluding 2017 and 2018, where a considerable decline was noticed. The results showed that Indian physiotherapists had mostly published in Indian-based journals, and collaborated with Indian institutions. Even though there are high-quality publications, there is a need to enhance both the quality and quantity of scientific papers to increase the high number of citations and average citations. This study also recommends that Indian physiotherapists should expand their research collaboration internationally to improve their scientific output.
Author 37: "…….though there are high-quality publications…" this stands as a mere claim and won't be meaningful without presenting the top-10 highly cited publications.
As advised, the top 10 highly cited papers are provided in Table 7 of the manuscript. A description of the top 10 highly cited papers is provided in the Results and Discussion section.
Refer to the Results section to see the changes made as follows: Besides, the top 10 highly cited papers during the study period were provided in Table 7

Methods:
How many reviews were collected in the articles, and what are their kappa score?
This study found 53 reviews by Indian physiotherapists during the period between 1999 and 2018. As this study only focused on revealing the scientific output of Indian physiotherapists in the WoS database, the authors did not explain the Kappa score for analysis and discussion.
Indian Physiotherapist means, who works only in India or Indian physiotherapists works throughout the world?
We mean those Indian physiotherapists who work in any of the academic or clinical establishments located in India (refer to article selection paragraph in the manuscript).
It is explained Under "Article Selection" of the Methods section The search was conducted on Oct 14, 2019. The term 'Indian physiotherapists' denotes physiotherapy professionals employed in any of the academic or clinical establishments in India in the study period. The search was carried out in WoS using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018". The search started from 1999 since this study aimed to retrieve data from the past two decades.
Selection criteria should be more specific.
We have included four selection criteria (i) Only those publications made by Indian Physiotherapist who works in India (subject understudy); (ii) Publications made between the year 1999 to 2018 (Timespan) (iii) database explored and the exact time where this search was carried out and (iv) key words used to retrieve the articles. (refer to article selection paragraph & figure 1)

Discussion:
The strength and limitations of this study are not mentioned.
The strength of this study is observed as the uptrend in the scientific output of Indian physiotherapists since 1999. It is mentioned in the conclusion section. Further, the limitations and recommendations of this study are mentioned under the heading "Limitations and Recommendations".
The following description is added Under 'Conclusion section.' This study observed that the scientific output of Indian physiotherapists shows an uptrend in performance since 1999, excluding 2017 and 2018, where a considerable decline was noticed. The results showed that Indian physiotherapists had mostly published in Indian-based journals, and collaborated with Indian institutions. Even though there are high-quality publications, there is a need to enhance both the quality and quantity of scientific papers to increase the high number of citations and average citations. This study also recommends that Indian physiotherapists should expand their research collaboration internationally to improve their scientific output.

The following description is added Under 'Limitations and Recommendations' section
The findings of this study are only limited to the WoS database. Future research can focus on studying the research output of the Indian physiotherapists in other databases to ascertain their research productivity. Future studies can focus on analyzing individual and institutional factors influencing the research productivity of Indian physiotherapists and develop suitable strategies to enhance their scientific production.

Conclusion:
Rephrase the Conclusion and make it more precise and clear.
The Conclusion is revised to improve the clarity of the readers as follows:

Under Conclusion
This study observed that the scientific output of Indian physiotherapists shows an uptrend in performance since 1999, excluding 2017 and 2018, where a considerable decline was noticed. The results showed that Indian physiotherapists had mostly published in Indian-based journals, and collaborated with Indian institutions. Even though there are high-quality publications, there is a need to enhance both the quality and quantity of scientific papers to increase the high number of citations and average citations. This study also recommends that Indian physiotherapists should expand their research collaboration internationally to improve their scientific output.

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